In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: Fix RPC client cleaned up the freed pipefs dentries
RPC client pipefs dentries cleanup is in separated rpc_remove_pipedir()
workqueue,which takes care about pipefs superblock locking.
In some special scenarios, when kernel frees the pipefs sb of the
current client and immediately alloctes a new pipefs sb,
rpc_remove_pipedir function would misjudge the existence of pipefs
sb which is not the one it used to hold. As a result,
the rpc_remove_pipedir would clean the released freed pipefs dentries.
To fix this issue, rpc_remove_pipedir should check whether the
current pipefs sb is consistent with the original pipefs sb.
This error can be catched by KASAN:
=========================================================
[ 250.497700] BUG: KASAN: slab-use-after-free in dget_parent+0x195/0x200
[ 250.498315] Read of size 4 at addr ffff88800a2ab804 by task kworker/0:18/106503
[ 250.500549] Workqueue: events rpc_free_client_work
[ 250.501001] Call Trace:
[ 250.502880] kasan_report+0xb6/0xf0
[ 250.503209] ? dget_parent+0x195/0x200
[ 250.503561] dget_parent+0x195/0x200
[ 250.503897] ? __pfx_rpc_clntdir_depopulate+0x10/0x10
[ 250.504384] rpc_rmdir_depopulate+0x1b/0x90
[ 250.504781] rpc_remove_client_dir+0xf5/0x150
[ 250.505195] rpc_free_client_work+0xe4/0x230
[ 250.505598] process_one_work+0x8ee/0x13b0
...
[ 22.039056] Allocated by task 244:
[ 22.039390] kasan_save_stack+0x22/0x50
[ 22.039758] kasan_set_track+0x25/0x30
[ 22.040109] __kasan_slab_alloc+0x59/0x70
[ 22.040487] kmem_cache_alloc_lru+0xf0/0x240
[ 22.040889] __d_alloc+0x31/0x8e0
[ 22.041207] d_alloc+0x44/0x1f0
[ 22.041514] __rpc_lookup_create_exclusive+0x11c/0x140
[ 22.041987] rpc_mkdir_populate.constprop.0+0x5f/0x110
[ 22.042459] rpc_create_client_dir+0x34/0x150
[ 22.042874] rpc_setup_pipedir_sb+0x102/0x1c0
[ 22.043284] rpc_client_register+0x136/0x4e0
[ 22.043689] rpc_new_client+0x911/0x1020
[ 22.044057] rpc_create_xprt+0xcb/0x370
[ 22.044417] rpc_create+0x36b/0x6c0
...
[ 22.049524] Freed by task 0:
[ 22.049803] kasan_save_stack+0x22/0x50
[ 22.050165] kasan_set_track+0x25/0x30
[ 22.050520] kasan_save_free_info+0x2b/0x50
[ 22.050921] __kasan_slab_free+0x10e/0x1a0
[ 22.051306] kmem_cache_free+0xa5/0x390
[ 22.051667] rcu_core+0x62c/0x1930
[ 22.051995] __do_softirq+0x165/0x52a
[ 22.052347]
[ 22.052503] Last potentially related work creation:
[ 22.052952] kasan_save_stack+0x22/0x50
[ 22.053313] __kasan_record_aux_stack+0x8e/0xa0
[ 22.053739] __call_rcu_common.constprop.0+0x6b/0x8b0
[ 22.054209] dentry_free+0xb2/0x140
[ 22.054540] __dentry_kill+0x3be/0x540
[ 22.054900] shrink_dentry_list+0x199/0x510
[ 22.055293] shrink_dcache_parent+0x190/0x240
[ 22.055703] do_one_tree+0x11/0x40
[ 22.056028] shrink_dcache_for_umount+0x61/0x140
[ 22.056461] generic_shutdown_super+0x70/0x590
[ 22.056879] kill_anon_super+0x3a/0x60
[ 22.057234] rpc_kill_sb+0x121/0x200
In the Linux kernel, the following vulnerability has been resolved:
fs/jfs: Add validity check for db_maxag and db_agpref
Both db_maxag and db_agpref are used as the index of the
db_agfree array, but there is currently no validity check for
db_maxag and db_agpref, which can lead to errors.
The following is related bug reported by Syzbot:
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:639:20
index 7936 is out of range for type 'atomic_t[128]'
Add checking that the values of db_maxag and db_agpref are valid
indexes for the db_agfree array.
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix array-index-out-of-bounds in diAlloc
Currently there is not check against the agno of the iag while
allocating new inodes to avoid fragmentation problem. Added the check
which is required.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: Fix possible null-ptr-deref when assigning a stream
While AudioDSP drivers assign streams exclusively of HOST or LINK type,
nothing blocks a user to attempt to assign a COUPLED stream. As
supplied substream instance may be a stub, what is the case when
code-loading, such scenario ends with null-ptr-deref.
In the Linux kernel, the following vulnerability has been resolved:
tty: vcc: Add check for kstrdup() in vcc_probe()
Add check for the return value of kstrdup() and return the error, if it
fails in order to avoid NULL pointer dereference.
In the Linux kernel, the following vulnerability has been resolved:
s390/dasd: protect device queue against concurrent access
In dasd_profile_start() the amount of requests on the device queue are
counted. The access to the device queue is unprotected against
concurrent access. With a lot of parallel I/O, especially with alias
devices enabled, the device queue can change while dasd_profile_start()
is accessing the queue. In the worst case this leads to a kernel panic
due to incorrect pointer accesses.
Fix this by taking the device lock before accessing the queue and
counting the requests. Additionally the check for a valid profile data
pointer can be done earlier to avoid unnecessary locking in a hot path.
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix potential deadlock when releasing mids
All release_mid() callers seem to hold a reference of @mid so there is
no need to call kref_put(&mid->refcount, __release_mid) under
@server->mid_lock spinlock. If they don't, then an use-after-free bug
would have occurred anyways.
By getting rid of such spinlock also fixes a potential deadlock as
shown below
CPU 0 CPU 1
------------------------------------------------------------------
cifs_demultiplex_thread() cifs_debug_data_proc_show()
release_mid()
spin_lock(&server->mid_lock);
spin_lock(&cifs_tcp_ses_lock)
spin_lock(&server->mid_lock)
__release_mid()
smb2_find_smb_tcon()
spin_lock(&cifs_tcp_ses_lock) *deadlock*
In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix slab-use-after-free in gfs2_qd_dealloc
In gfs2_put_super(), whether withdrawn or not, the quota should
be cleaned up by gfs2_quota_cleanup().
Otherwise, struct gfs2_sbd will be freed before gfs2_qd_dealloc (rcu
callback) has run for all gfs2_quota_data objects, resulting in
use-after-free.
Also, gfs2_destroy_threads() and gfs2_quota_cleanup() is already called
by gfs2_make_fs_ro(), so in gfs2_put_super(), after calling
gfs2_make_fs_ro(), there is no need to call them again.
In the Linux kernel, the following vulnerability has been resolved:
virtio-blk: fix implicit overflow on virtio_max_dma_size
The following codes have an implicit conversion from size_t to u32:
(u32)max_size = (size_t)virtio_max_dma_size(vdev);
This may lead overflow, Ex (size_t)4G -> (u32)0. Once
virtio_max_dma_size() has a larger size than U32_MAX, use U32_MAX
instead.